Block #510,343

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 4/25/2014, 2:34:59 PM · Difficulty 10.8244 · 6,294,972 confirmations

2CC
Cunningham Chain of the Second Kind

A sequence where each prime is double the previous prime minus one.

Block Header
Block Hash
03d6c9b0af49eb47a7b2316a9a4de6ab4b0df7d9899434d9fe911121651025ee

Height

#510,343

Difficulty

10.824437

Transactions

5

Size

1.37 KB

Version

2

Bits

0ad30e47

Nonce

520,761

Timestamp

4/25/2014, 2:34:59 PM

Confirmations

6,294,972

Merkle Root

89fbc34a6d44ee1dc1ea0c5bdabccc01b342d27a65a1d53e99481a32af078f76
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

3.406 × 10⁹⁵(96-digit number)
34068179710581428836…40405934830673808641
Discovered Prime Numbers
p_k = 2^k × origin + 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

1
origin + 1
3.406 × 10⁹⁵(96-digit number)
34068179710581428836…40405934830673808641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.813 × 10⁹⁵(96-digit number)
68136359421162857672…80811869661347617281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.362 × 10⁹⁶(97-digit number)
13627271884232571534…61623739322695234561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.725 × 10⁹⁶(97-digit number)
27254543768465143068…23247478645390469121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
5.450 × 10⁹⁶(97-digit number)
54509087536930286137…46494957290780938241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.090 × 10⁹⁷(98-digit number)
10901817507386057227…92989914581561876481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.180 × 10⁹⁷(98-digit number)
21803635014772114455…85979829163123752961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
4.360 × 10⁹⁷(98-digit number)
43607270029544228910…71959658326247505921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
8.721 × 10⁹⁷(98-digit number)
87214540059088457820…43919316652495011841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.744 × 10⁹⁸(99-digit number)
17442908011817691564…87838633304990023681
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 consecutive prime numbers forming a Cunningham Chain of the Second Kind. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

★★☆☆☆
Rarity
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)
Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,686,598 XPM·at block #6,805,314 · updates every 60s
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